Superconductivity

Experiments:

"An introduction to superconductivity" by Alfred Leitner originally published in 1965, source: www.alfredleitner.com/
Isotope effect on the critical temperature. hyperphysics.phy-astr.gsu.edu/hbase/Solids/coop.html mentions that:
If electrical conduction in mercury were purely electronic, there should be no dependence upon the nuclear masses. This dependence of the critical temperature for superconductivity upon isotopic mass was the first direct evidence for interaction between the electrons and the lattice. This supported the BCS Theory of lattice coupling of electron pairs.

Lectures:

Video 1. 20. Fermi gases, BEC-BCS crossover by Wolfgang Ketterle (2014) Source. Part of the "Atomic and Optical Physics" series, uploaded by MIT OpenCourseWare.
Actually goes into the equations.
Notably, youtu.be/O_zjGYvP4Ps?t=3278 describes extremely briefly an experimental setup that more directly observes pair condensation.
Video 2. Superconductivity and Quantum Mechanics at the Macro-Scale - 1 of 2 by Steven Kivelson (2016) Source. For the Stanford Institute for Theoretical Physics. Gives a reasonable basis overview, but does not go into the meat of BCS it at the end.

Lecture notes:

Media:

www.supraconductivite.fr/en/index.php#supra-explication
Cool CNRS video showing the condensed wave function, and mentioning that "every pair moves at the same speed". To change the speed of one pair, you need to change the speed of all others. That's why there's not energy loss.

Transition into superconductivity can be seen as a phase transition, which happens to be a second-order phase transition.

 Tagged